Mercedes-Benz W140 S-Klasse Used Vehicle Review

W140 Exterior

The Mercedes S class is the pinnacle of luxury cars, it's the car you look at to find out what you may expect in ten years from lesser cars. The W140 is on the list because it's a car that is unique in the way it drives, rides and handles. Upon first inspection of the car you realize it's enormous, and you'd be right as it's the largest S Class Merc has ever made. It was designed to take on Rolls Royce at the time and needed to be large enough to fit the wealthy owner comfortably in the back. The second thing you may notice is it's not exactly good looking but it does have quite a presence, I'm willing to overlook the so-so looks because the interior and drive makes up for it. After I drove this car I quickly realized that at some point in my life I want to own an S-Class, maybe it will even be the first one!

As I mentioned above Mercedes always fills these cars with notable features making it innovative in some way. The big features of the W140 S class included double pane glass creating an insulated window which would help avoid condensation and filter our exterior noises, self closing doors and trunk which could pull themselves shut when gently latched, a rest function that would circulate heat for up to 20 minutes after the engine was shut down, up to four zone climate control on higher end models, 12 way electric seats, Parameter steering allowing easier maneuvering in parking lots by reducing input effort, and park distance control. A lot of these features are found on cars these days at much lower prices but in the 90s these features were unheard of, and very high tech. 

W140 Interior

The interior of the W140 is first rate everywhere, lots of leather, wood and thick carpet, everything is well made and stands the test of time extremely well, it also includes all the goodies you would expect in a car today such as heated seats, automatic climate control, ability to set different zones for each person, high end Bose audio system etc. Unfortunately though the interior is where some issues crop up likely due to vehicle age. Things like power locks and windows may fail. Mercedes uses a compressed air/ vacuum system to actuate the locks so it has what is called a PSE pump (Pneumatic systems equipment pump) under the passenger rear seat with a little electric motor to create a vacuum or compression to actuate the locks unfortunately this little motor tends to fail over time due to years of service. It can be replaced though for under $10 making it a fairly cheap fix if you're willing to do it yourself. If you're not willing to do the job yourself a dealer will replace the entire pump costing a few hundred of your dollars. Other possible issues leading to failed locks include leaks in the vacuum lines, leaks in the tank itself (unlikely, but possible) or leaks in the connectors from the pump to the lines. Replacing the lines in the car could be tricky as they weave through the entire car but if you're willing to do the work you can save a fair bit of coin. A second PSE pump is also used for the gentle close doors and is located in the trunk it works in a similar manner as the one under the back seat and also has the tendency to fail with age, the same problems above are common culprits. It's important to check all electronics in the W140 you're looking at due to the number of electric goodies in these cars, it could be something as simple as a fuse but also could be the component itself that has bit the dust so before buying be sure they work.

Other common problems are also generally associated with age including rough idle or possible stalling which can be due to a mass airflow sensor, bad spark plugs, spark plug wires, or coil packs. This is not at all a problem with Mercedes quality though and will simply occur because these cars can be 20 years old now and with time these parts just wear out. Keep in mind it will be expensive if you take it to the dealer or a similarly trained Mercedes mechanic to have fixed. Performing these repairs yourself can be relatively inexpensive as parts aren't as expensive as you might think (coil packs are under $100 for example). Some of these jobs will not be for the faint of heart however as they require you to take a fair portion of the engine apart, if you're not the type of person who likes to open the hood and check things out you should budget for dealer trips when something goes wrong.

Vehicles costs apart from repair and maintenance aren't the cheapest due to the fact that most of these vehicles come equipped with V8 engines (more on the engines later) and require premium gas, and when I say require I don't mean you should put it in but can use regular - I mean you must use it to avoid replacing engine parts because it is known to foul up spark plugs and mass air flow chambers so budget for premium fuel when looking at these vehicles. Gas mileage it self is quite good considering the size and weight of this vehicle (some weigh close to 5000 pounds!). City mileage as you would expect does suffer but getting north of 25 MPG on the highway isn't a rare occurrence, some people admit to getting over 30 MPG while highway cruising. As true with any car your fuel mileage is more to do with your driving style than the vehicles itself.

On to the engines. In North America there were 4 engine choices for the W140 including a 3.2L inline six producing 228hp and 229 lb/ft, a 4.2L V8 producing 275hp and 295 lb/ft, a 5L V8 producing 315hp and 348 lb/ft, and finally a 6L V12 producing 389hp and 421 lb/ft. Out of these engines there are two I would avoid, the first being the inline 6 due to low power output coupled with a heavy car, and the V12 because it's known for many issues and is very costly to repair as well as being difficult to work on because the W140 was designed for V8s and it is crammed in the engine bay. The 4.2 and 5 make great choices both producing good power and delivering reasonable fuel economy.

After reading the last few paragraphs most of you are probably thinking there's a lot wrong with this car it just looks like a big expense. While it's not the cheapest car it does redeem itself in many regards, the main one is the drive. W140s drive extremely well, they have a planted fell which I've never experienced in anything else, yet they also soak up bumps while travelling on less than stellar roads (a common occurance in Ontario). The handling of the car is a bit surprising because you don't expect such a large car to go around corners very well yet this car somehow does, and it does so without getting upset or losing composure. The engine is smooth, well balanced and will pull strong from just 1000 RPM, a trait I love about Mercedes. The car even starts off in second gear when being driven normally to ensure the start from a stoplight is as smooth as can be, and will only drop into first when really prodded. It's a vehicle that likes to chug along at about 1300 RPM and will shift below 2000 making it almost silent. The brakes are very smooth and powerful despite being burdened with the weight of this beast. It's a car I feel that was built to be the best it could be, corners weren't cut in the name of cost savings and it shows when driving one, every control is silky smooth and operates beautifully, frankly I can't understand why you would buy this car only to sit in the back.